Alex Iwobi, Sead Kolasinac reap rewards of Unai Emery's bold Arsenal tinkering

Not for the first time this season, Unai Emery made the first move an hour before the match had begun. If the Arsenal head coach has shown one thing since arriving in north London, it is that he is not afraid to make bold decisions, and here was another one: Mesut Ozil had been dropped to the bench, and Arsenal were going to play with a back three.

It was only the second time that Emery has so drastically changed his shape this season. The first was away to Qarabag in the Europa League, and the experiment was abandoned after 45 minutes, seemingly written off as an error that would not be repeated.

Yet here we were again,  against an energetic and organised Bournemouth side  that would provide far more of a test than Qarabag. This was a risk, then, but it led to great reward for Emery and Arsenal, who scored two goals that provided obvious vindication for the reshuffle.

Both of their strikes, an spectacular own goal from Jefferson Lerma and a poacher's finish from Pierre-Emerick Aubameyang, were the result of Emery’s new shape. Both were created by Alex Iwobi and Sead Kolasinac, the two players who benefited most clearly from the change of system.

With the freedom to drift into a more central position, Iwobi was Arsenal's chief creative threat. His impressive start to the season has tailed off in recent weeks, but here he buzzed and floated around the final third with genuine menace. Unai Emery switched to a three-man defence for the trip to Bournemouth – and it paid off Credit: Getty images

He was helped by the flying Kolasinac alongside him. His excellence was further proof – as if it were still needed – that he is far more of a threat (and far less of a liability) in a wing-back position. As a more traditional left-back, as he was in the recent draw with Wolves, Kolasinac plays with the air of a man on the verge of destruction at any moment. As a wing-back, though, he looks liberated.

The contrast is bizarre, but it is irrefutable. It was no more obvious than on the south coast, when Kolasinac streaked forward to assist both of Arsenal's goals with driven crosses. The second, scored by Aubameyang, was slick, quick and devastatingly direct. It was just how Emery likes it.

Of course, there were problems. This was no stroll for Arsenal, who needed a combination of fortune and fortitude to cling onto the three points. Indeed, it had taken them around 20 minutes, at least, to come to grips with what they were trying to do. Rob Holding in particular was in need of time – and plenty of encouragement from the manic Emery on the touchline – to adapt to his unfamiliar role on the left side of the Arsenal defence.

But adapt he did, to an extent, and so did Arsenal. For much of the opening period they looked encouragingly assured. In fact, as first-half performances go, this was probably one of Arsenal's better showings of the season.

Alongside Iwobi, Lucas Torreira and Granit Xhaka had seized control of the central areas, and Sokratis and Shkodran Mustafi were, by and large, winning their individual battles. But Arsenal are yet to fully shake off the defensive frailties that so undermined the final years of Arsene Wenger's reign, and they were out of and shape and out of touch for the Bournemouth equaliser before the break. Joshua King's curling effort meant that, remarkably, Arsenal have still not been leading a Premier League game at half-time this season.

It did not matter here, and the best part for Arsenal is that it rarely looked like it would. Once they had regained the lead, they treated the usual late scares with composure. Emery even perched on the advertising hoardings, as relaxed as he had been all game, when Bournemouth had a late free-kick.

Arsenal were helped by a tremendous second-half showing from Aubameyang, who followed up his winning goal by running and striving and bringing his team-mates into play. It was far removed from his recent performances on the left-wing, and it will only add to questions over whether he and Alexandre Lacazette, absent here through injury, can truly work together.

Those issues, though, are for another day. The focus here should be on one of Arsenal's best performances of the season, a run of 17 games unbeaten in all competitions, and a victory for a head coach who tinkered to great effect.